1. Field of the Invention
The present invention relates to a mechanical therapeutic apparatus. More particularly, it relates to percussive vibrators used in chiropractic care.
2. Prior Art
Percussion is a treatment modality for those who suffer from problems such as musculoskeletal pain and myofascial trigger syndrome. It is non-surgical, non invasive procedure that may serve as a therapeutic alternative to trigger point and epidural injections or to be used when other treatments have failed.
There are many known devices that facilitate treatment or change in soft and hard tissue. A common element of these devices is that they tend to be small and hand held to facilitate use. For the device to work properly it must also be powerful enough to effect the necessary force to be therapeutic. A side effect of the combination of small size and power are the problems associated with excess heat generated by instruments in use.
Excess heat leads to shortened component life, and may add to discomfort in the use of the device.
Devices in the field of the invention are by their nature under extensive amounts of mechanical stress in their normal course of use. The nature of a vibrating tool makes the addition of a fan or other additional cooling apparatus difficult. In addition the adding any new moving member to such a tool adds to the potential of component failure and noise.
The present invention is directed to this shortcoming in the prior art in that it provides for quiet cooling at low cost, without adding additional components which may be subject to failure. The invention is also a means for providing cooling in vibratory or reciprocating tools of many other fields.
It is an object of the present invention to provide a percussive vibrator tool with quiet improved heat dissipating qualities.
The operation and benefit of the invention is to use the vibrating or reciprocating arm component to provide the percussive force of the invention and the impelling force to pump air through the device to provide cooling.
The body of the vibrator is a sealed case which serves as an air chamber. It is fitted with one or more one-way air valves. A reciprocating arm, or vibratory impeller is attached to a sealed diaphragm to permit vibration of an impact head while maintaining a largely air tight seal.
As the impact head is moved, the volume of the body of the vibrator oscillates. Air is permitted to enter at one point fitted with a one-way air valve on expansion, and expelled on retraction or contraction. The body of the vibrator essentially operates as a pump.
While multiple check valves may be used, an inexpensive and preferred option is to use a single air valve at one point, and small or air limiting restrictive openings at another. These restrictive openings may be one or more small holes that limit air flow so that on body volume expansion, air enters through the one-way air valve and the holes, but on contraction, there is a net movement of air as air moves out only through the air holes.
To effect a greater volume of net air flow and greater cooling, the volume of the air space in the vibrator should be kept as small as possible relative to the tidal volume created by the vibratory impeller. Though the entire body of the vibrator may be used as the air chamber or housing, for greater efficiency a divider plate or other divider may be used to create a smaller air chamber or housing surrounding the reciprocating components. In the preferred embodiment of the invention this is accomplished by limiting the air chamber or housing to the immediate vicinity of the reciprocating arm, with the air inlet and one way valve placed on the top of the device, and small restricted air holes placed on a divider plate, isolating the air chamber from the motor and circuitry to be cooled.
Air is pumped by the reciprocating arm through the housing and into the remainder of the body of the vibrator to cool the motor and any circuitry.
For a more complete understanding of the present invention, reference is made to the following detailed description and accompanying drawings.